Laser-induced ESR shift of a paramagnetic transition metal complex ion [IrBr6]2−

Taking a paramagnetic transition metal complex ion [IrBr6]2− as an example, the laser-induced ESR shifts in oriented and unoriented samples have been studied and calculated. In oriented and unoriented systems the ESR shifts result from the contribution of the symmetric and antisymmetric polarizabilities. The shifts of the [IrBr6]2− complex ion are calculated to be of the order of 1∼10 kHz for a laser beam of 10 W cm−2. The factors affecting the magnitude of the laser-induced ESR shift are discussed. The results indicate that there should be observable ESR shifts in a molecular or radical paramagnetic system on applying linearly or circularly polarized light at a frequency near optical absorption.